$$2{F_2} + 4KOH \to 4KF + {O_2} + 2{H_2}O$$        for 1 $$mole$$  of $${F_2}$$  the molar ratio.
$$\eqalign{ & {F_2}\,\,\,\,\,\,KOH\,\,\,\,\,\,KF\,\,\,\,\,\,{O_2}\,\,\,\,\,\,{H_2}O \cr & 1\,\,\,\,\,\,\,\,\,\,\,\,\,2\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2\,\,\,\,\,\,\,\,\,\,\frac{1}{2}\,\,\,\,\,\,\,\,\,\,\,\,1 \cr} $$

In case of $$N{\left( {Si{H_3}} \right)_3},N$$    atom is $$s{p^2}$$  hybridised, the lone pair is present in $$2p$$  orbital and it is transferred to empty $$d$$  orbital of $$Si$$  forming $$d\pi - p\pi $$   bond. Hence nitrogen with $$s{p^2}$$  hybridization has trigonal planar shape.

In the reaction

Nitrogen can form $$NC{l_3},{N_2}{O_5}C{a_3}{N_2}$$     and not $$NC{l_5}$$  since it has no $$d$$  atomic orbitals in valence shell

\[\underset{\text{Acidic}}{\mathop{{{P}_{4}}{{O}_{10}}}}\,+2{{H}_{2}}O\to \underset{\begin{smallmatrix} \text{meta phosphoric} \\ \text{acid} \end{smallmatrix}}{\mathop{4HP{{O}_{3}}}}\,\]      \[\xrightarrow[\text{basic}]{N{{H}_{3}}}\underset{\begin{smallmatrix} \text{meta ammonium} \\ \text{phosphate} \end{smallmatrix}}{\mathop{N{{H}_{4}}P{{O}_{3}}}}\,\]

$$\eqalign{ & \mathop {PC{l_5}}\limits_{\left( A \right)} + {H_2}O \to \mathop {POC{l_3}}\limits_{\left( B \right)} + 2HCl \cr & \mathop {POC{l_3}}\limits_{\left( B \right)} + 3{H_2}O \to \mathop {{H_3}P{O_4}}\limits_{\left( C \right)} + 3HCl \cr} $$

Gallium $$(Ga)$$  with unusually low melting point $$\left( {303\,K} \right),$$  can exist in liquid state during summer. Its high boiling point $$\left( {2676\,K} \right)$$  makes it a useful material for measuring high temperature.

\[\begin{align} & \text{Borax}\xrightarrow{HCl}{{H}_{3}}B{{O}_{3}} \\ & {{B}_{2}}{{O}_{3}}\xrightarrow[\Delta ]{Al}B\,\text{(crystalline)} \\ & {{B}_{2}}{{O}_{3}}\xrightarrow[\Delta ]{Mg}B\,\text{(Amorphous)} \\ \end{align}\]

$$C{l_2} + 2B{r^ - } \to B{r_2} + 2C{l^ - }$$
Bromide ion when treated with $$C{l_2}$$  gas then form chloride ion and $$B{r_2}$$  gas liberated.

Due to the inert pair effect ( the reluctance of $$n{s^2}$$  electrons of outermost shell to participate in bonding ) the stability of $${M^{2 + }}$$ ions ( of group 14 elements ) increases as we go down the group.